You’ve been feeling lousy for months. Your head and muscles ache and sleep doesn’t relieve the numbing exhaustion. Could you have chronic fatigue syndrome? We answer 11 questions about this mysterious illness and detail symptoms, treatments and more…

Women juggle so much daily, it’s no surprise they feel dragged down occasionally. But ongoing, crushing fatigue, even if you’re getting lots of rest, could signal a little-understood illness called chronic fatigue syndrome (CFS).

The syndrome — which strikes 500,000 Americans, most of them women — involves debilitating fatigue that lasts longer than six months, unrelieved by sleep. Physical or mental activity may drain your energy even more, forcing you to cut back dramatically in activities. Every movement feels like you’re dragging a sack of weights around with you.

The bad news? CFS can’t be cured. But you can get relief from its symptoms. Here are our answers to 11 common questions about this perplexing condition:

1. What are the most common chronic fatigue syndrome symptoms?Besides the constant fatigue, CFS has eight “official” symptoms:

Sore throat

Painful and possibly enlarged lymph nodes in the neck and/or in the armpits

Memory loss or difficulty concentrating

Unexplained and persistent muscle pain

Unexplained joint pain that may move from one joint to another. (They’re not red or swollen.)

Unexplained headaches of a new type or severity

Sleep that doesn’t refresh you

Extreme exhaustion lasting more than 24 hours after mental or physical activity. (The fatigue can come and go.)

Symptoms can come on gradually or suddenly and are the same in men and women.

2. What causes CFS?Despite extensive research, we don’t know.

One prominent theory is that a trigger – such as a virus, an attack on the immune system or a problem with part of the endocrine system – causes the body to respond with chronic fatigue syndrome symptoms.

At one time, the illness was also known as Chronic Fatigue and Immunodeficiency Syndrome (CFIDS) because doctors believed that people with the syndrome had a dysfunctional immune system. Studies have found immune system irregularities but no consistent pattern.

3. Who’s at risk? Why is it more common in women? CFS occurs in both genders, but women are four times more likely to have it. No one knows why yet.

Although CFS affects adults of all ages, it most commonly strikes people in their 40s or 50s.

Those with other illnesses appear to be more susceptible because their bodies' defenses are already weakened.

4. Does family history play a role?Several members of a family can sometimes have CFS, so a genetic component is possible. But this, too, needs further study.

5. How is CFS diagnosed?Unfortunately, no single test can confirm a CFS diagnosis. Instead, doctors must try to exclude all other causes of symptoms similar to chronic fatigue syndrome symptoms. This involves testing for anemia, liver disease, infection and many other conditions.

The “workup” includes extensive blood tests, neurological and psychological testing, and in some cases, a biopsy of the lymph nodes as well as imaging studies like X-rays or computed tomography (CT) scans. (The latter are cross-sectional images of the body.)

You probably have CFS if:

Your tests are normal and you have at least four of the eight official CFS symptoms

Your fatigue has been present for at least six months

All other possible causes of your symptoms have been excluded

Because identifying CFS is difficult, it’s important to see a rheumatologist,an infectious disease specialist or a physician experienced in diagnosing the illness.

6. Why is testing to exclude other illnesses so important?Most – if not all – of the other illnesses with symptoms similar to chronic fatigue syndrome symptoms can be treated or cured. Obviously, treating any illness as soon as possible is important.

7. Why are the illness and its diagnosis controversial?For several reasons: The name causes confusion because fatigue that is chronic or long lasting may not always stem from CFS.

Because no single test can diagnose CFS and symptoms vary by patient, the diagnosis is difficult and time-consuming. Somepatients don’t even complete the workup.

Also, before researchers defined CFS, many clinicians didn’t believe it was a specific illness. So there was much confusion about the syndrome within the medical community.

The result: Patients were often misdiagnosed or undiagnosed. Many clinicians still don’t understand CFS and its definition.

The illness has emotional burdens as well: Because CFS can be invisible, patients often don’t look sick, leading some people to think they’re imagining symptoms.

8. Can a person who has always had a low energy level have CFS?No. A person with CFS fatigue experiences a big change in energy and activity that can be sudden or gradual.

9. Is CFS similar to Epstein-Barr, fibromyalgia or other autoimmune diseases?Many chronic fatigue syndrome symptoms resemble those of infections, fibromyalgia and autoimmune diseases. But these other diseases in their entirety aren’t like CFS.

For instance, fatigue, sore throat and painful lymph nodes also occur in mononucleosis, which can be caused by the Epstein-Barr virus (EBV). But mononucleosis or EBV infections don’t usually cause the other symptoms that can come with CFS.

The muscle and joint pain and fatigue can be similar to fibromyalgia and some autoimmune diseases, such as lupus. With fibromyalgia, the joint and muscle pain are the most prominent. In CFS, fatigue is the most severe symptom.

10. What treatments or drugs are available?Since CFS has no known cause, doctors treat the symptoms rather than the illness. For example, tricyclic antidepressants, such as amitryptilline can help themood and sleep problems and joint and muscle pain.

There are more medications used to treat other CFS symptoms as well. (Consult your physician immediately if additional symptoms appear after you’ve started a prescribed drug.)

Alternative therapies, such as acupuncture, water therapy, massage and yoga, appear to help relieve symptoms. Ask your physician about these.

11. Are there lifestyle or diet changes that will help?Absolutely. A healthy lifestyle is your treatment, so modifying your habits is extremely important to lessen chronic fatigue syndrome symptoms.

For starters, limit your regular activities. (We’ve often recommended that our CFS patients take sick leave or temporary disability for weeks or months.)

Rest often, but also do some physical exercise, such as light stretching and strength training. Start slowly and exercise for only several minutes each day at the beginning.

Learning to pace yourself is also key. Since depression is common, pay attention to moods and emotional health, seeking help from a therapist if necessary.

If you’re sleeping poorly, examine your habits. Set a routine time to go to bed and get up each day. Don’t balance your checkbook right before you snooze either. Instead, take a warm bath or listen to soothing music in the minutes before lights out.

When you feel stress coming on, try this calming exercise: Close your eyes, breathe in deeply through your nose and slowly exhale through your mouth several times.

Eating a healthy diet of whole grains, fruits, vegetables and low-fat proteins is always important but especially for anyone with a chronic illness.

If you have gastrointestinal symptoms, eliminate the foods that seem to make symptoms worse.

Some CFS patients improve enough from lifestyle changes to resume their activities. Of course, if you jump back into a hectic schedule once you feel better or discontinue the basics of a healthy lifestyle, chronic fatigue syndrome symptoms can reappear.

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